package com.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import com.model.Staff;

public class CommonInterceptor implements HandlerInterceptor {

	/**
	 * 在业务处理器处理请求之前被调用 
	 * 如果返回false 从当前的拦截器往回执行所有拦截器的afterCompletion(),再退出拦截器链
	 * 如果返回true 执行下一个拦截器,直到所有的拦截器都执行完毕 再执行被拦截的Controller 然后进入拦截器链,
	 * 从最后一个拦截器往回执行所有的postHandle() 接着再从最后一个拦截器往回执行所有的afterCompletion()
	 */
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
		//执行顺序: 1、preHandle
		Staff s = (Staff) request.getSession().getAttribute("sessionStaff");  
		
        if(s==null){  
        	String uri = request.getRequestURI();
        	String subUri = uri.substring(uri.lastIndexOf("/")+1);
        	System.out.println(subUri);
        	if("login.action".equals(subUri)){
        		System.out.println("------true-----");
        		return true;
        	}else{
        		response.sendRedirect("/meijia/login.jsp"); 
        		System.out.println("------false-----");
                return false; 
        	}
        	   
        }  
        
        
        return true;
        
	}

	// 在业务处理器处理请求执行完成后,生成视图之前执行的动作
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
								ModelAndView modelAndView) throws Exception {
		//执行顺序: 2、postHandle ...
		// System.out.println("--------postHandle----------");
	}

	/**
	 * 在DispatcherServlet完全处理完请求后被调用
	 * 
	 * 当有拦截器抛出异常时,会从当前拦截器往回执行所有的拦截器的afterCompletion()
	 */
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, 
			Object handler, Exception ex) throws Exception {
		
		//执行顺序: 3、afterCompletion
		//System.out.println("--------afterCompletion----------");
	}
}


